EVK-ANNA-B112 - User Guide
UBX-18018539 - R01
Product description
Page 11 of 29
Connector
annotation
Add jumper
to pins
Description
J7
3, 4
Selects the diode protected battery as a source for the VDD_ANNA net.
9, 10
(Optional) Powers up the Interface MCU, USB hub, and UART to USB converter with 3.3 V.
J22
1, 3
Powers up the ANNA module. The ANNA VCC and VCC_IO pins are connected to the selected
source for the VDD_ANNA net.
2, 4
(Optional) Powers up the peripherals directly connected to ANNA such as LEDs and external
memory with the ANNA supply voltage.
Table 5: Jumper positions for battery powered operation with a protection diode, two jumpers are optional
1.6.5
External supply
When measuring current consumption or performing other ANNA-B112 module characterization
measurements, it can be useful to power the module with an external source such as a DC power
analyzer. In such a case, all jumpers can be removed and the required supply nets can be fed
externally by connecting to the pin headers. For example, the ANNA-B112 module can be powered by
connecting an external supply directly to the J22 pin 1 and GND.
☞
Take care that unpowered parts of the board are properly isolated. If a voltage is applied to the
signal of an unpowered device, current might leak through various protection circuits of the
device. This might give false readings when measuring current consumption etc.
Figure 11 below shows a few optional jumper connections that can be helpful when supplying the
module with an external supply.
Figure 11: Optional jumper positons while using an external power supply
Connector
annotation
Add jumper
to pins
Description
J7
7, 8
(Optional) Selects the board regulated 3.3 V net as a source for the VDD_ANNA net.
9, 10
(Optional) Powers up the interface MCU, USB hub, and UART to USB converter with 3.3 V.
J22
3, 4
(Optional) Powers up the peripherals directly connected to ANNA such as LEDs
and external memory with the selected source for the VDD_ANNA net.
Table 6: Optional jumper positons while using an external supply
1.6.6
Raspberry Pi HAT
When connecting a HAT to the Raspberry Pi interface, the following jumper configuration can be
used. Depending on how the ANNA module should communicate with a test PC over USB or with the
HAT, the VDD_MCU net can be left unpowered.
The 3V3_PI supply net must only be powered when connecting to a Raspberry Pi expansion board
(HAT). If connecting to a Raspberry Pi board, the jumper must be disconnected.
Figure 12: Jumper configuration when connected to a Raspberry Pi HAT
